SCOTLAND should have its own currency up and running on day one of independence, the think tank Common Weal has claimed.

The left-wing pro-independence campaigners also warned that sticking to the SNP Growth Commission’s plan to keep sterling for at least a decade after a Yes vote would mean being tied to the pound until 2039.

Their report comes just days before Keith Brown holds the first of three “National Assemblies,” set up by the SNP to specifically discuss the economic blueprint for independence pulled together by former MSP Andrew Wilson.

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That report recommended Scotland retain sterling as its currency if it voted to leave the UK, and to then transition to plans for setting up a new currency over ten years.

In their proposals Common Weal say the Scottish currency could be launched much sooner.

“If Scotland does not launch its own currency, it will be beholden to rules made by the Bank of England without there being any obligation for those rules to take Scotland’s

economic needs into account,” the report says.

It adds: “Scotland would also be reliant on London financial institutions loaning Scotland the money it needs to function. If and when another financial crisis affects London, an independent Scotland needs to be able to protect itself. Only by having its own currency can Scotland build the independent country that it wants to build.”

Common Weal say that as its analysts think it “will likely take around three years to negotiate a leaving agreement with the UK and to build all of the infrastructure that Scotland needs” that should allow “sufficient time to build the new currency.”

They argue that the Scottish currency should initially be pegged 1:1 with the UK pound as this will mean no change in prices.

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They also claim that the Growth Commission’s plans would likely result in Scotland being without its own currency for 15 years.

“This means that if Scotland votes to become independent in 2021 and takes three years to become an independent country, it would be 2039 before that country had its own currency,” the report says.

The campaign is backed by The National columnist and former SNP MP George Kerevan. He called on all “supporters of Scottish independence to back the Common Weal campaign for a Scottish currency.”

Nicola Sturgeon defended the Growth Commission’s proposals on currency soon after the report was published – though she did not explicitly back Sterlingisation.

The First Minister rejected comparisons with countries such as Panama and Ecuador who use the US dollar without any say on US monetary policy.

During an interview with Politico, Sturgeon said: “If Scotland was to use the pound outwith a currency union, even for a transitionary period, I don’t think it puts us in the same position as Panama, for example.

“The term Sterlingisation that is often used is when a country chooses to use a currency that is not its own. The pound is Scotland’s currency right now, the pound as everybody knows is a fully tradeable international currency.”

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In the run-up to the 2014 referendum, Alex Salmond argued Scotland would be able to use the pound in a formal currency union. That was immediately rejected by the Treasury and all the pro-UK parties.

But earlier this year Bank of England Governor Mark Carney told MPs on the Treasury select committee that such an arrangement could be possible.

There was no mention of the Growth Commission in the SNP’s draft agenda for their annual conference, much to the annoyance of some supporters. But Brown, the SNP’s depute leader, insisted the National Assembly events would “open a fresh conversation of hope, ambition and how an independent Scotland can be a fairer, more prosperous country.”